Electrical heating unit



F. J. GROVEN ELECTRICAL HEATING UNIT Filed Nov.v 12,' 1920 I q LL I 1-Tj ffql.

WITNESS:

l ATTORNEY.

Patented Aug. 7, 1923.

UNITED STATES PATENT OFFICE.

FRIEDRICH J. GROVEN. 0F HIGHLAND PARK, MICHIGAN, ASSIGNOR T0 FORD MOTOR COMPANY, OF HIGHLAND PARK, MICHIGAN, A CORPORATION OF DELAWARE.

ELECTRICAL. HEATING UNIT..

Application filed November 12, 1920. Serial No. 423,561.

T 0 all wiz-om it may concern.'

Be it known that I, Frommen J. GROVEN, a citizen of the United States, residing at Highland Park, in the county of Vayne and State of Michigan, have invented new and useful Improvements in an Electrical Heating Unit, of which the following is a speeiication.

The object of my invention is to provide an improved electrical heating unit of simple, durable and inexpensive construction.

A further object of my invention is to provide a heating unit of especially compact construction which will give a maximum length of servicev with a minimum amount of current consumption and a minimum amount of adjustment.

A further object of my invention is to 4provide a heating unity comprising a bar of material having a high electrical resistance and to insulate this bar of material from the device in which it is installed to thereby permit said device to be heated from the heat generated due to the resistance of said fas bar.

A further object of my inventionis to provide aresistance unit comprising a plurarilty of portions of varying diameters made from material of high electrical resistance whereby the resistance to electri-I cal current may be separated into a number ot spaced portions of the unit to thereby spread out the heat generated by the unit over a considerable area.

A further object of my invention is to provide a heating unit comprising a series of pieces of material of high electrical resistance which contact with each other in such a way that the places of contact may be of less cross sectional area than are the remaining portions of the pieces.

A further ob ject oi my invention is to provide a heating unit especially adapted for soldering irons or 'other objects requiring continuous heating for considerable apparatus or time, comjirising an insulated sleeve having my improved resistance unit therein. whereby one end oi the resistance may be, connected with a source of current and the other end grounded into the frame or body of the soldering iron or the like.

A further object of my invention is to provide in such a device means for maintaining the pieces of the heating unit in constant contact with each other.

A further object ot' my invention is to provide means for insulating the handle of the heated object against the electrical currents and also against the heat generated by the unit.

lith these and other objects in view, my invention consists in the arrangement, combination, and construction of the various parts of my improved device, as described in the specification, claimed in my claims, and shown in the accompanying drawings, in which:

Figure 1 is a vertical, sectional View through my improved device, the heating unit being in this instance illustrated as installed in a soldering iron, .and

Figure 2 is a diagrammatic View illustrating the construction and wiring of my improved heating unit.

Referring to the accompanying drawings, I have used the reference numeral 10 to indicate, generally, a feed wire for my improved iron, having a pairof current carrying wires 1l and 12 therein. A handle member 13 comprises a solid blockof heat insulating material and a cap member 14 of similar material fixed to the end thereof by the screws 15. Screwed into the handle 13 are a pair of rods 16 and 17, which have their remaining ends screwed into cap 18. The cap 18 is internally screw threaded to receive the threaded end ofa hollow soldering point 19, which may be of any suitable shape to perform the operation of soldering. In this connection it should be mentioned that while l have shown this heating unit as installed in a soldering iron, it is adapted for heating substantially any form oi' device which can be heated by electrical means.

The hollow portion or recess of the soldering member 19 terminates in aconical portion 20. The body portion ot' this recess receives a sleeve 21 of electrical insulating material which extends from position adjacent to the cap 18 to position adjacent to the conical portion 20. Loosely received within the sleeve 21 are a plurality of segments 22 and 23, which form my heating unit and which, in the form here illustrated, are composed of cylindrical pieces of carbon of substantially the diameter of the interior of the a point at 24. The end segment 2,3 is here illustrated as being somewhat longer than then the remaining segments and it lits closely into the conical recess 20, thereby grounding that end of the heating unit into the so dering member.

A push rod 25 is slidably mounted in hole 26 drilled. through the handle 13 and has iis ends adjacent to said end electrically connected with a wire 12. Sutlicient length is allowed for the Wire 12 to permit some movement of the rod 2G Without tending to fatigue the Wire 12 too greatly. The push rod 25 passes through an opening 2 in the central portion of the cap 18 and contacts with. the end segment 22 Within the sleeve 21. The opening 26 in the handle 13 is enlarged 28 somewhat to receive coiled spring 29, which coacts with the bottom olf recess 28 and a in 30 which is lined in the push rod 25 yieldmgly urge said push rofl toward said heating unit segments. The Wire 11 passes into hole 31 in the side of the cap la and continues to position where it may be electrically connected With one or both et the rods 16 at 32. If desired this Wire 11 may pass through. a hole drilled in the walls of the cap lfl and the handle 13.

In Figure 2 I have illustrated a wiring diagram for use in connection with my heating unit in which the wires 33 lead from a source of electrical energyv (not shown) to a transformer 35i. From the transformer 34; the wires l1 and 12 lead to the ends of my heatin unit.

In igure 2 l have also illustrated in dotted lines the construction of the soldering iron here shown to better illustrate the connection between the electrical circuit and the heating unit, but it will be understood that I do not intend to limit myself thereby to the use of this heating unit With the particular structure shown. It will also be noted that I do not desire to limit my invention to the particular material here mentioned, carbon, but that any material having substantially the qualities of carbon, i. e., high electrical resistance, may be used in the place thereof. The heating unit need not be comosed of a plurality of segments but may be ormed of a continuous bar.

I do not desire to limit myself to the particular form of supporting and insulating the heating unit here shown, as other means maybe used which may accomnlish the same result.

Some changes may be made in the arrange ment and construction of the various parts ot my improved device Without departing from the spirit of' the invention therein and it is my intention to cover by my claimsy such changes as may be reasonably included Within the scope thereof.

I claim as my invention:

1. In an electrical heating device, a resistance unit comprising a bar of material of relatively high electrical resistance, said bar having constricted portions therein, and means for establishing an electrical circuit therethrough.

2. In an electrical heating device, a resistance unit comprising a bar of material of relatively high electrical resistance, said har having constricted portions therein, means for holding said bar from movement, and means for establishing an electrical circuit through said unit.

3. In an electrical heating device, a resistance unit comprising a bar of material of relatively high electrical resistance, said bar having constricted portions therein, a sleeve oi electrical insulating material adapted to hold said har from lateral movement, and means 'tor establishing an electrical circuit throu h said unit.

ll. n a device of the class described, a casin g having an opening therein, a sleeve of insulating material within said opening, and a resistance unit comprising a bar having constricted portions and formed `from matem rial having relatively high electrical resistance, and means for establishing a circuit through said unit.

5. In a device of the class described, a handle member composed of electrical and heat resisting material, a plurality of su portin rods extended therefrom, a ca memher fixe' to said supporting rods, sai cap member having a central opening therein, a casing detachably secured to said cap, anl insulatnfr sleeve Within said casing, a resistance unit slidably mounted in said sleeve, a push rod slidably mounted in said handle in posi tion to contact with one end of said resistance unit, and means for yeldingly'urging said push rod into contact with said resistance unit to thereby force 1t into contact' with the casing.

FREDRICK J. GROVEN. Witness:

EDWARD L. DAVIS. 

